A composite, especially a nanocomposite material comprising a conductive filler and an organic or polymer matrix, can be used to measure local mechanical strain by detecting the change in electrical conductivity and capacitance induced by said strain. It can be used in a broad array of applications where local strain or strain change; pressure or pressure change; or displacement, deformation, bending, or flexing, need to be measured. With a well calibrated temperature coefficient of the material and the device, it can also be used as a temperature sensor to measure local temperature change. With a well calibrated strain humidity relationship of the material and the device, it can also be used as a humidity sensor to measure local humidity.
The field of use for such a nanocomposite material includes but is not limited to force sensing and controls in any human machine interface for smart phones, tablets, personal computers, touch screens, virtual reality (VR) systems, gaming systems, consumer electronics, vehicles, scientific instruments, toys, remote controls, industrial machinery, bio-medical sensors to monitor heart rate, blood pressure, and the movements and acceleration of muscles, bones, joints and other body parts; robotic sensors to measure touch, local pressure, local tension, movements and acceleration of any parts of the robots; vibration sensors for buildings, bridges and any other man-made structures; sensors to monitor strain, pressure, movement, acceleration of any parts of vehicles that may be used in land, air, water, or space; movement, acceleration, and strain sensors that can be incorporated into smart fabrics; movement, acceleration, and force sensors that can be incorporated into microelectromechanical (MEMS) systems, and any other applications where local static or dynamic deformation, displacement, or strain need to be measured.
In this patent we propose a nanocomposite sensing materials with low aspect ratio conductive fillers with close to or higher than percolation threshold in a low Poisson's Ratio matrix binder with a high gauge factor, low temperature coefficient of resistance (TCR), low temperature coefficient of gauge factor (TCGF), and low hysteresis.